Non-volatile mercaptan and hydroxyamine impregnated end wrap and method of use



Jan. 20, 1959 R. s. MOORE 2,869,559

NON-VOLATILE MERCAPTAN AND HYDROXYAMINE IMPREGNATED END WRAP AND METHOD OF USE Filed Oct. 7, 1957 IN VENTOR BY QaTao-w, a e. AMfz. 7 42? ATTORNEY-5 Patented Jan. 20, 1959 NON-VOLATILE MERCAPTAN AND HYDROXY- AMINE lMPREGNATED END WRAP AND METHOD OF USE Robert S. Moore, Wyoming, Ohio, assignor to The Procter &f glaimble Company, Cincinnati, Ohio, a corporation 0 Application October 7, 1957, Serial No. 688,682 12 Claims. (Cl. 132-7) This invention relates to cold waving of hair. More particularly it relates to permeable sheets impregnated with keratin-reducing compositions.

The so-called cold permanent waving of hair is in part accomplished by contacting the hair with some chemical composition which will soften and plasticize it Without the use of heat. According to the present understanding in the art such chemical compositions reduce the keratin structure of the hair, thereby breaking disulfide linkages present in the keratin. While the reduced hair is held in a desired configuration the disulfide linkages are restored by an oxidation step thereby tending to hold the hair tresses in the new configuration.

The advantages of cold permanent waving and the disadvantages of waving processes which require heat are well known. Cold waving lotions have been developed in the art which eliminate the need for the complicated heating arrangements, the long treating and waving time and the risk of hair damage from the heat waving processes. Nevertheless, cold waving processes have certain disadvantages.

ln commonly used prior art cold waving processes the hair is saturated with a keratin-reducing solution and wound around curlers or other suitable devices. After sufiicient time has elapsed to effect desired hair reduction, the hair is rinsed and neutralized by chemical or air oxidation. The manipulation of hair saturated with such reducing solutions is messy and difficult. Some irritation to the hands may result from continued contact with the solution, if the time required for winding the hair on curlers is excessive, or from frequent uses of the solution.

In another prior art process the hair tresses are wound about curling devices, and a keratin-reducing solution is then poured over the wound tresses or introduced onto the outside of the tresses in some manner. When this process is used, it is difficult to obtain a uniform saturation of the air. The outside of a wound tress will receive a heavy concentration of the lotion, while the portion of the hair inside a wound curl will receive a much smaller amount. As a result, portions of the hair may be damaged by the too high concentration and other parts of the hair may not be waved at all because they are not contacted by sufficient lotion to break the disulfide bonds.

It has now been found that keratin-reducing compositions may be applied to the hair easily and conveniently by means of the impregnated sheets of this invention. The impregnated sheets containing the components necessary for hair reduction are placed in contact with hair tresses, and the tresses are wound about curlers. The wound curls are saturated with water which dissolves the keratinredncing composition from the impregnated sheets and the solution becomes dispersed throughout the curl to react with the keratin of the hair. After the disulfide linkages are broken the action of the reducing composition is stopped and the disulfide linkages are reformed by rinsing the hair and neutralizing it either chemically or by air. The provision of impregnated sheets which are efiective, safe, economical, practical and easy to use is not without problems and difficulties.

Accordingly, it is one of the objects of this invention to provide a novel, improved and simple means for waving hair.

Another object is to provide impregnated sheets suitable for cold hair waving having the proper concentration and type of hair waving chemicals whereby the sheets are stable, safe and effective and so pliable and non-brittle that the sheets can be easily manufactured and used.

A further object is to reduce the hand and skin irritation associated with prior art cold waving procedures.

ln general, this invention comprises a thin, pliable permeable sheet impregnated with a substantially nonvolatile, water-soluble, keratin-reducing composition which consists essentially of a mercaptan and a substantially non-volatile, hydroxyamine alkaline buffering material in a sufiicient amount to maintain the composition at a pH of between 8.5 and 10 when the composition is dissolved in water and is in contact with the hair.

The drawing represents a series of similar hair tresses waved under conditions varying in intensity as indicated by the arbitrary value assigned to each tress, more fully described hereinafter in Example IV.

The term impregnated as used in connection with the sheets of this invention is intended to include a coating of the keratin-reducing composition on the surface of the sheet, and a coating on individual fibers as well as the filling up of interstices between the fibers.

The term pliable as used in connection with the sheets of this invention means that the sheets can easily be bent and rolled with hair tresses into curls of ordinary size and tightness without the sheets cracking or breaking. Moreover, the pliable sheets should not be so resilient that they cannot be easily rolled and the curls held in place by the common curlers and hairpins.

The permeable sheets of this invention can be cloth or paper. The sheets should be of a material which will be inert toward the keratin-reducing composition. It has been found that materials such as Wool, woolen flannel, felt, and cellulose acetate will react with mercaptans or alkaline materials and are, therefore, generally unsuitable. Cellulose materials such as paper made from purified flax or cloth made from purified cotton (batiste) have been observed to be substantially inert toward mercaptans and alkaline materials and are suitable in other respects.

The sheets should be sufliciently porous to permit passage through the sheets of the aqueous solution used to dissolve the keratin-reducing composition, and also to permit passage through the sheets of subsequent rinsing solutions or other solutions used to restore the disulfide linkages. The sheets should not be so absorbent that the passage of solutions through the sheets is unduly inhibited. This permeability can be achieved by using a loosely woven structure where there is spacing between the individual fibers. Cloth or paper of the non-woven type may also be used. If the sheets are closely woven or do not posses sufiicient inherent permeability they may be provided with a plurality of perforations.

The sheets should be of such a size and shape that theycan at least partially encircle tresses of hair. The sheets may be long enough to extend the entire length of hairtresses or may only cover the ends of hair tresses in themanner of so-called end wraps.

The sheets should be between about .005 and about- Sheets thinnerthat sheets thicker than about .005 inch are too thick and.

bulky to be handled and processed easily and donot result:

inthe desired pliabilityandpermeability characteristics after impregnation.

The keratin-reducing composition with which the sheets are impregnated-must 'besubstantially non-volatile. This prevents evaporation of the composition prior to use ofthe sheets and-"alsoreduces the odor-of the-mercaptans and alkaline agen'tsp The*'composition--sho'uld also be water-soluble in order that it can be activated by merely mercapto prop'i'onic acid, m'e'rcapto butyricacid and men capto-cap'r'oic--acidand the -water soluble salts-thereof.

Examples of suitable merc'aptans which are operative in the invention-are thioglycolic acid, sodium thioglycoiate, potassium thioglycola-te, m'onoethanolamine tizioglycolate, ,e-mercaptoisobutyric: 'acid," thiohydracrylim acid, p-mer capto n-bu'tyric acid, a-me'rcaptocaproic' acid, and thiolactic acid.

lt'has been found that the amount of mercaptan present in the sheets of 'thisinvention should be in an amount equivalentto from about .003 gram to about .020 gram of thioglycolic acid per square inch of sheet. If mercaptan equivalent to'less than about .003rgram of thioglycolic acid per square inch is present, a satisfactory wave will not be formed. if mercaptan equivalent to more than about .020 gram of thioglycolic acid per square inch is present, the hair structure may be damaged.

Although this range has been found critical for the cold waving of an average amountof ordinary hair in the usual sized hair tress, and is therefore essential to the production of waving materials intended for general use, it must be appreciated that this range can be modified to include the amount of-mercaptan to safely wave varying sizes and types of hair. Moreover, the amounts of mercaptan usefulfor safely and effectively waving hair. vary somewhat with the time the mercaptan is in contact with the hair, i. e., lesser concentrations of mercaptan require a longer contact time to reduce hair, but the risk of hair damage is much less than when higher concentrations of mercaptan which reduce the hair more rapidly are employed. The above-mentionedrange is based on the usual, practical hair-waving periods.

In addition to the mercaptans it may be desirable to include in the keratin-reducing composition a watersoluble 'disulfide of the mercaptan used such as dithiodiglycolic acid, dithiodilactic acid, the disulfides of B-mercapto butyric acid, S-mercaptoisobutyric acidor u-mercaptocaproic acid, dithiodihydracrylic acid or a watersoluble salt of these'to protect against excessive reduction and damage of the hair, in accordance with the disclosures in U. S. Patent 2,719,814 issued to Haefele and U. S.'Patent 2,719,815 issued to Sanders on October 4, 1955;

Duringthe time that the keratin-reducing composition is in the form, of a solution-in contact with the hair it is preferable that the pH be maintained between 8.5 and 10. This is accomplished by the presence of a substantially non-volatile alkaline bufferingmaterial as a component of the keratin-reducing composition with which the sheets are impregnated. The alkaline buifering material should not react unfavorably with the hair or with the components of the keratin-reducing composition.

The-alkaline buffering materials commonly used in hair wavinglotions such as ammonia, methylamine and ethylamine werefound to be unsuitable for processing,

storage and use of the impregnated sheets because they.

. changes in the wavingcompositions during the treatment of the hair.

It was found that sodium or potassium carbonate pro-- vide a suitably constant pH when they are used as the alkaline material in the keratin-reducing composition impregnated in the sheets of this invention. However, thesecarbonates -were observed to have other characteristics' which make them-unsuitableforuse inthe impregnated keratin-reducing composition'ofthe sheets of this invention. dioxide on-standin'g:or. heating and thus increase the alkalinity. The greatest difficulty encountered when attempting to use carbonates as alkaline bufiering agents for the impregnated sheets of this invention is that thebrittlef ness, that results from the crystalline character of the the impregnated sheets ofthisinvention. They are cX- Such cellent alkaline bufiers' for hair-waving purposes. hydroxyam-ines do not impart a brittle crystalline charactei to-the impregnated sheets. In fact, they are Waxy, i. e. solid to viscous-liquid in nature when impregnated in the' sl1eets.. The impregnated sheets, therefore are easily processed on machinery and are very pliable in use.- The hydroxyamines' suitable for use in this invention are" of the formula C(RIRIIRIII) wherein X is selected from the group consisting of hydrogenvand alkylol radicals containing 1 to 3 carbon atoms, R and R". are each selected from the group consisting of hydrogen, alkyl radicals containing 1 to 3 carbon atoms and alkylol. radicals containing 1 to -3 carbon atoms and R" is analkylol radical containing 1 to 3 carbon atoms.

Thehydroxyamines which have been found to be especially suitable in the impregnated sheets of this invention are:

Monoethanolamine N'o'oHzoH Trishydroxymethylaminoethane H. CHQOH' NCCH2OH H CHZOH 2-amino-2-methyl-1,3-propanediol H 1 CHzOH NCCH3 H omoH Examples" of other suitable hydroxyamines are:

Diethanolamine i o oniorr ciomolr Carbonates have a tendency to lose carbon" This . 7 amountsofu'potassium dithiodigly'colate. The alkaline materialwasadded.afterthis reaction was complete.

Percent Potassium thioglycolate 22.0 Potassium dithiodigly'colate 10.5 Trishydroxymethylaminomethane 16.5 Water 51.0

A paper: made 'sfrompurified flax, Ecusta #527, weighing 32gramsper square meter,-about .0025 inch thickand 32 inches wide, was run through the above solution from rolls at'a rate-of about 50 yards per minute.

Thepaper: wasgently squeezed' between 'rolls, scraped with angle bars and then continuously dried in an oven. The. sheets were slit-into 3 inch widths and cut into 3 inch squares andhad'the -following approximate composition':

When these sheets were used to wrap hair tresses which were thenwound about hair curlers and saturated with water, the impregnated composition dissolved and reduced the hair substantially as shown in Example 1. After rinsing and. neutralization withan aqueous solution of sodium perborate, an excellent hair wave resulted from treatment with the acid of the impregnated sheets of this example.

Amounts of thiohydracrylicacid, a-mercaptocaproic acid and B-mercapto-n-butyric acid and their corresponding vdisulfideequivalent in keratin-reducing power to the amounts ofpotassium thioglycolate and potassium dithiodiglycolate shown in this example can be-used in place of theseasalts with substantially equal results. Moreover, amounts of diethanolamine, Z-amino-l-butanol, 2- amino-Z-methyl-l-propanol and monoisopropanolamine equivalent in alkalinity to the amount of trishydroxymethylaminomethane shown in this example can be used in place of this alkaline bulfering agent with substantially equal results.

Example IIl.-Sheets impregnated with the following ingredients were produced by dipping the paper into on aqueous solution of these ingredients and drying the impregnated sheets to about 5% moisture. The sheets were used to obtain excellent hair waves in the manner described in Example 11 above.

The paper used was made from purified flax, Ecusta #500', was about .0012 inch thick and weighed about 16 grams per square meter. Thesheets were cut into 3 inch squares 'andhadthe following weights of impregnated Sheets B, C, and D illustrate how increasing quantities of-inercaptancanrbeused to obtain stronger-hair waving action-'or shorter hair waving time. Thesesheets also illustrate that the quantity ofalkaline agent is ordinarily increased with increasing mercaptan content. The protective"dithiodiglycolicacid is ordinarily about half the amountof'-thioglycolicacid. on'asquare'inch basis a preferred composition range of sheets impregnatedwith' the above ingredients is about as follows.

Grams Thioglycolic acid present as potassium salt .005 to .008 Dithiodiglycolic acid present as the potas:

sium salt .0025 to .004

Trishydroxymethylaminomethane .005 to .008

The preferred ratio by weight of the above ingredients is about 221:2 in the 'order'listed. The preferred thickness of sheet material before'impregnation is in the range of about .001 to about .003 inch? Example IV.T0 determine the-range of mercaptan which can be impregnated in the sheets of this invention to obtain a satisfactory wave without damaging the hair, paper made from purifiedflax was impregnated with trishydroxymethylaminomethane and the potassium salts of thioglycolic acid and dithiodiglycolic'acid by dippingthepaper into an aqueous solution of these ingredients, drying the paper to about 5% moisture and cutting them into 3 inch square sheets. The papers were used to wave tresses of hair in accordance with the method previously described.

To determine damage'to thehair tr'esses the standard 20% "index test described in 'U'. S.Patent 2,719,815 issued to J. H. Sanders onOctober 4; 1955was used.

To determine the degree of wave, the wave grade photoscale shown in thedrawing was used. The'photoscale-comprisesnine wet switches of hair which had been,

cold waved tovarying ,degrees of tightness in approximately a'linear relationship by adjusting either the timeof waving, strength of the waving lotion or'both. The

switches were made from the same type of ordinary Thickness, Weight in Paper inches Grains Per Square Meter- Grams Per 3 x 3 Square Sheet Wave 20% Paper Trishy-- Grade Index Result Thiogly- Dithlodldroxycolic glycolic' methyl- Acid Acid aminomethane 0183 0092 0183 2. 75 90 Under- A waved. 027 0135 027 2. 75 92 Do.

. 212 .106 212 6.0 711 Damaged. 0235 0118 0235 2. 5 91 Underwavedn B 028 014 028 3. 0 84 Good wave.

. 17 085 17 5. 25 Do. 018 009 018 2.0 91 Underp I waved. C .019 0095' .019 2. 25 .92 Do.-

091 0455 091 v 4. 6 Good wave. .10 .095 .19 5.5 .71 Damaged.

1 Potassium thioglycolate calculated as thioglycolic acid.

3 Potassium dithiodiglycolate calculated asdithiodlglycolic acid. Through experience-ithas been found that a satisfactory wave must 'have' awave grade" of about, three or greater but-lessthan eight and that a non-damaging wave must have a 20%"index'of'ab'out180 or greater. Therefore, from the above kda't'atand'the previous'examples it was determined that a satisfactory" and "safe range "of" mer 2-arnino-2-ethyl-1,3-propanediol H c1120]; N-CLC 1H6 H CHzOH Z-amino-l-butanol i I H n \NCCC 2H5 n onion Z-amino-Z-methyl-l-prop anol V H CHzOH N-C-CH:

H CH:

Monoisopropanolamine Sufficient alkaline materials should be included in the keratin-reducing composition which is impregnated in the sheet to maintain a pH in the range of 8.5 to while the composition is in solution and is in contact with the hair tress. The pH within these ranges, for optimum hair waving, is determined by the concentration of mercaptan in the composition and the time selected for the waving process. The time of Waving has been described as being shorter with higher concentrations of mercaptan and longer with lower concentrations of mercaptan. The time of waving is also less at higher pH values and longer at lower pH values. Moreover, effective waving can be done at lower pH values if the concentration of the mercaptan is increased. If the concentration of the mercaptan is decreased the pH values should be higher to obtain effective waving action. It has been found that the concentrations of the substantially non-volatile hydroxyamine alkaline materials of this invention, especially monoethanolamine, trishydroxymethylaminomethane and 2-amino-2-methyl-1,3-propanediol, easily can be adjusted to the optimum pH for a particular mercaptan concentration and a corresponding waving time.

The concentration of the mercaptan and alkaline buffering material in the impregnated sheets should be adjusted so that, by, adding water to make a solution of the compounds, a satisfactory hair wave is obtained during a given time of application without damage to the hair within the desired pH range by providing that higher concentrations of mercaptan are used at lower pH values and lower concentrations of mercaptan are used at higher pH values. For example, when a satisfactory hair wave is safely obtained with a given amount of thioglycolic acid at a pH of 9.2, it takes about one and a half as much at a pH of 8.9 and about two thirds as' much at a pH of 9.5 to safely obtain approximately the same wave.

Additional materials can be added 'to the keratin-reducing composition on the sheets, such'as lanolin, lanolin derivatives, perfume, wetting agents, dyes, binders and plasticizers, but these. materials are not essential to the invention described herein.

The sheet material may be conveniently impregnated by use of a water solution of' the keratin-reducing composition. The sheet material may be passed through the water solution, or the solution may be brushed or sprayed onto the sheet-material. v The impregnated sheet is then dried by means of an air blast, drum dryer, oven, or other suitable means to remove excess moisture. If too much water is removed, the sheet material may tend to crack or break, and it has been found that the presence of at least about 2% moisture is necessary to keep the sheets pliable and keep them from becomingbrittle .the air.

' monohydrate acidified to a pH of 5.7.

the mercaptans and alkaline agents, for example by exces-,

sive heating, a lower limit of about 2%. moisture is also desirable in this respect.

'It has been found that excessive moisture in the im pregnated sheets unduly encourages oxidation of the mercaptan to the disulfide if the sheets are left exposed to This reduces thewaving effectiveness of the sheets. It has been found that up to about 10% moisture in the sheets will allow very satisfactory stability in air for a length of time equal to average life before use.

The impregnated material in sheets of this invention containing more than about 10% moisture tends to rub off on the hands during use. It has been found that if the sheets contain greater than about 10% moisture they are also too messy for practical use. This condition tends to reduce some of the outstanding advantages of the sheets of this invention including their simplicity, lack of m-essiness and lack of irritation to the hands; Moreover, excessively moist sheets tend to stick together and greatly reduce the ease with which they ordinarily can be handled and used.

In order to prevent volatilization during drying, perfume, if employed, is preferably added to the sheet material after the drying step is completed.

'The following examples will illustrate the invention with greater particularity, but it is not'limited thereto. Parts and percentages are by weight.

Example I.An aqueous solution was prepared con taining the following materials:

Ecusta Type 234 was passed through this solution. The paper was three inches wide and 0.002 inch thick, and was provided with perforations ,6, inch in diameter uniformly spaced in a pattern containing 42 perforations per square inch; After the paper had passed through the aqueous solution it was air-dried in a drying tunnel. After the drying step was completed the paper was cut into strips three'inches long. The material incorporated in each 3 inch by 3 inch impregnated sheet weighed about .093 gram and had the following composition.

7 Percent Sodium thioglycolate 39.5 Sodium dithiodiglycolate 30.0 Monoethanolamine 25.0

Water 5.5

The hair 'of a testsubject'was washed and towel-dried. The hair was divided into tresses, and a single impreg nated sheet was-wrapped around each tress extending from the end of the tress toward the scalp. Each wrapped tress was then wound on a curler and secured. When all the tresses had been wound, all were saturated with water. After waiting 15 minutes the hair was rinsed thoroughly with water. After an additional 30 minutes the hair was neutralized with an aqueous solution of sodium perborate The hair was again rinsed with water, removed from the curlers, set in a normal fashion, and dried. A uniformly soft wave was obtained. V r

Similar results can be obtained by substituting monoethanolamine thioglycolate and dithiodiglycolate, for the sodium salts in the above example.

Example II.An aqueous solution having the following composition was prepared by mixing potassium thioglycolate with enough hydrogen peroxide to obtain the stated captan equivalent to thioglycolic acid in the impregnated sheets is from about, .003 to about .020 gram per square inch.

In any of the foregoing examples the dithiodiglycolates can be omitted from the keratin-reducing compositions impregnated in the sheets without reducing the advantages and the efiectiveness of the sheets. The effect of such omission merely would require a more careful gauging by the user of the sheets, of the time that the impregnated sheet can be left in contact with the hair Without the risk of hair damage.

Itis to be understood that the action on the hair of the mercaptan in the keratin-reducing composition impregnated in the sheets of this invention can be neutralized by chemical compounds such as bromates, perborates, or hydrogen peroxide, or by the action of air alone.

The application is a continuation-in-part of my copending application Serial No. 550,469, filed December 1, 1955 now abandoned.

What is claimed is:

1. As an article of manufacture useful in cold waving hair, a permeable, pliable sheet impregnated with a substantially non-volatile, water-soluble, keratin-reducing composition, said composition containing a mercaptan selected from the group consisting of mercapto-acetic acid, mercapto-propionic acid, mercaptobutyric acid, mercaptocaproic acid and water-soluble salts of these distributed throughout said sheet in an amount equivalent to from about .003 to about .020 gram of thioglycolic acid per square inch of said sheet and sufiicient substantially nonvolatile, hydroxyamine alkaline material to maintain said composition within a pH range of 8.5 to when said composition is in solution and in contact with the hair said hydroxyamine having the formula C (R! RUB!!!) wherein X is selected from the group consisting of hydrogen and alkylol radicals containing 1 to 3 carbon atoms, R and R" are each selected from the group consisting of hydrogen, alkyl radicals containing 1 to 3 carbon atoms and alkylol radicals containing 1 to 3 carbon atoms and R is an alkylol radical containing 1 to 3 carbon atoms, the concentration of mercaptan and said alkaline material being adjusted to obtain a hair wave during a given time of application without damage to the hair by having the concentration of mercaptan in the higher portion of said thioglycolic acid range for a lower pH within said pH range and having the concentration of mercaptan in the lower portion of said thioglycolic acid range for a higher pH within said pH range, said sheet being between about .005 and about .0005 inch thick before impregnation, being inert toward said composition and containing from about 2% to about 10% moisture.

2. The article of manufacture according to claim 1 wherein the hydroxyamine alkaline material is selected from the group consisting'of monoethanolamine, trishydroxymethylaminomethane and 2-amino-2-methyl-l,3- propanediol.

3. The article of manufacture according to claim 2 wherein the mercaptan is monoethanolamine thioglycolate.

4. The article of manufacture according to claim 2 wherein the mercaptan is sodium thioglycolate.

5. The article of manufacture according to claim 2 wherein the mercaptan is potassium thioglycolate.

6. As an article of manufacture useful in cold waving hair, a permeable, pliable sheet impregnated with a keratin-reducing composition consisting essentially of about .005 to about .008 gram of thioglycolic acid present as the potassium salt, about .0025 to about .004 gram of dithiodigly'colic acid present as the potassium salt and about.005 to about .008gram of trishydroxymethylaminomethane per square inch of said sheet, said ingredients having the ratio by weight of about 2:1:2, said sheet being paper made from purified flax and about .001 to about .003 inch thick before impregnation and containing from about 2% to about 10% moisture.

7. The method of imparting a wave to hair without the use of heat which comprises the steps of forming the hair into tresses, wrapping about each tress a permeable, pliable sheet containing from about 2% to about 10% moisture, said sheet being impregnated with a substantially non-volatile, water-soluble, keratin-reducing composition, said composition containing a mercaptan selected from the group consisting of mercapto-acetic acid, mercapto-propionic acid, mercapto-butyric acid, mercapto-caproic acid and water-soluble salts of these distributed throughout said sheet in an amount equivalent to from about .003 to about .020 gram of thioglycolic acid per square inch of said sheet and a substantially nonvolatile hydroxyamine alkaline material, said hydroxyamine having the formula wherein X is selected from the group consisting of hydrogen and alkylol radicals containing 1 to 3 carbon .atoms, R and R" are each selected from the group consisting of hydrogen, alkyl radicals containing 1 to 3 carbon'atoms and alkylol radicals containing 1 to 3 carbon atoms and R is an alkylol radical containing 1 to 3 carbon atoms, winding each wrapped tress about a curler, said moisture range in said sheet resulting in a lack of messiness during use, saturating each tress with water whereby said keratin-reducing composition is dissolved and thereafter neutralizing the action on the hair of said keratin-reducing composition, said alkaline material being sufficient to maintain said composition within a pH range of 8.5 to 10 when said composition is in solution and in contact with the hair, the concentration of said mercaptan and said alkaline material in said sheet being adjusted to obtain a hair wave during a given time of application without damage to the hair by having the concentration of mercaptan in the higher portion of said thioglycolic acid range for a lower pH within said pH range and having the concentration of mercaptan in the lower portion of said thioglycolic acid range for a higher pH within said pH range.

8. The method according to claim 7 wherein the hydroxyamine alkaline material is selected from the group consisting of monoethanolamine, trishydroxymethylaminomethane and 2-amino-2-methyl-1,3-propanediol.

9. The method according to claim 8 wherein the mercaptan is monoethanolamine thioglycolate.

10. The method according to claim 8 wherein the mercaptan is potassium thioglycolate.

11. The method according to claim 8 wherein the mercaptan is sodium thioglycolate.

12. As an article of manufacture useful in cold waving hair, a permeable, pliable sheet impregnated with a substantially non-volatile, water-soluble, keratin-reducing composition, said composition containing a water-soluble salt of mercapto-acetic acid distributed throughout said sheet in an amount equivalent to from about .003 to about .020 gram of thioglycolic acid per square inch of said sheet and 2-amino-2-methyl-l,3-propanediol in amount to maintain said composition within a pH range of 8.5 to 10 when said composition is in solution and in contact with the hair, the concentration of the salt and the amine being adjusted to obtain a hair wave during a given time of application without damage to the hair by having the concentration of salt in the higher portion of said thioglycolic acid range for a lower pH within said pH range and -having the concentrationof=-"'sa lt in' thelower portion'of'said thioglycolic-acid i'an'ge for-a higher pH Within 'said-pI I-rangqsaid sheet 'bein'g btweemaboub .005 and about .0005 inch thick before impregnation,

being inert'toward Said'compusition and containing from about 2% to-about 10% moisture.

References Cited "in the? file of this patentz: UNITED STATES "PATENTS 1,531,291 Ingr-assia ,Mar. 31, 1925 1,607,981 Grotf Nov. 23, 1926 1,637,469 Brown Aug.,2,. 1927:

OTHER REFERENCES 1 Helene Curtis Cold Wave Instruction Booklet, No.1103 (a), Jan..23, 1945,.esp.,at pp; 2 and 4.

UNITED STATES PATENT OFFICE QERTIFICATE Q8 ECTEGN Patent Noa 2,869,559 January 20, 1959 Robert S 0 Moore It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 51 for "air" read W hair column 4 line 55 9 for "Trishydroxymethylaminoethane read Trishydroxymethylaminomethane' =-1= column '7 line 45, for "into on" read m1 into an e Signed and sealed this 5th day of May 1959.

(SEAL) Attest:

ROBERT C. WATSON KARL H0 JDCLINE Commissioner of Patents Attesting Officer UNITED STATES PATENT OFFICE CERTIFICATE OF (IORRECTION Patent Noa 2,869,559 January 20, 1959 Robert 50 Moore s in the-printed specification It is hereby certified that error appear tion and that the said Letters of the above numbered patent requiring correc Patent should read as corrected below.

Column 1, line 51 for "air" read hair column 4 line 55, for

Trishydroxyilietlhylamino'ethane" read em Trishydroxymethylaminomethan r "into on" read me into an u column 7, line 45, f0

Signed and sealed this 5th day of May 1959 (SEAL) Attest:

ROBERT C. WATSON KARL AXLINE Commissioner of Patents Attesting Officer 

7. THE METHOD OF IMPARTING A WAVE TO HAIR WITHOUT THE USE OF HEAT WHICH COMPRISES THE STEPS OF FORMING THE HAIR INTO TRESSES, WRAPPING ABOUT EACH TRESS A PERMEABLE, PLIABLE SHEET CONTAINING FROM ABOUT 2% TO ABOUT 10% MOISTURE, SAID SHEET BEING IMPREGNATED WITH A SUBSTANTIALLY NON-VOLATILE, WATER-SOLUBLE, KERATIN-REDUCING COMPOSITION, SAID COMPOSITION CONTAINING A MERCAPTAN SELECTED FROM THE GROUP CONSISTING OF MERCAPTO-ACETIC ACID, MERCAPTO-PROPIONIC ACID, MERCAPTO-BUTYRIC ACID, MERCAPTO-CAPROIC ACID AND WATER-SOLUBLE SALTS OF THESE DISTRIBUTED THROUGHOUT SAID SHEET IN AN AMOUNT EQUIVALENT TO FROM ABOUT .003 TO ABOUT .020 GRAM OF THIOGLYCOLIC ACID PER SQUARE INCH OF SAID SHEET AND A SUBSTANTIALLY NONVOLATILE HYDROXYAMINE ALKALINE MATERIAL, SAID HYDROXYAMINE HAVING THE FORMULA 